1. Field of the Invention
The present invention relates to an electrophotographic image forming apparatus that forms an image on a recording medium.
2. Description of the Related Art
A color electrophotographic printer is known which includes a plurality of image forming units, each unit including a photoconductive drum, a charging unit, an exposing unit, and a developing unit. One such apparatus is a tandem color printer disclosed in Japanese Patent Application No. 2011-39378. Black (K), yellow (Y), magenta (M), and cyan (C) image forming units are aligned along the transport path of a print medium. As the print medium passes through the image forming units in sequence, toner images of corresponding colors are transferred onto an intermediate transfer belt in registration. The toner images are then transferred onto print paper fed in timed relation with the formation of the respective toner images.
When a color image is formed on a recording medium having a color other than white, a white toner may be used to hide the color of the recording medium. However, a color toner transferred onto the white toner can be mixed with the white toner, impairing a desired image quality.